1. Technical Field of the Invention
The present invention relates to a sheet transporting speed control apparatus and more particularly to a sheet transporting speed control apparatus preferably applicable to a control system when a document to be transported is delivered in the transporting systems which are controlled in constant speed by a plurality of independent control systems.
2. Brief Description of the Prior Art
In a copying machine including an image processor and a sorter, for instance, when the sorter receives a paper discharged from the image processor, a transporting speed of the sorter is arranged to be faster than that of the image processor because it is difficult to completely match the speeds with each other and paper jam is feared when the speed of the sorter is delayed since they are controlled by different control systems.
At the time when a paper is transported from an image processor to a sorter, if a state of pulling each other is generated, the sorter tends to carry the paper in full power in order to correct the lowered speed since the speed of sorter is set faster than that of the image processor, whereby the paper is torn and causes backlash and chipping of gear in the image processor to result in bad influence on an image.
In order to prevent such problems, the device has heretofore been arranged to increase restraint to a pulling torque by a mechanical structure providing with a mechanism such as sliding clutch in a drive transmission section in the sorter. However, the cost becomes too expensive since such mechanical structure is so complicated, and especially, there remain problems in the functional stability of a sliding clutch.